Surfacing machine



April 1964 I D.'R. TALBOTT 3,130,653

SURFACING MACHINE Filed April 4, 1961 INVENTOR DAVID R TALBOTT E .5 BY am a ATTORNEYS United States Patent 3,139,653 SURFA-CftNG MAQHTNE David R. Taibott, 224 Westwood Road, Annapoiis, Md. Filed Apr. 4-, 1961, Ser. No. 106,626 7 Ciaims. (Ci. ?4-4-5) This invention relates to surfacing machines and more particularly to improved rotary power driven apparatus which is especially, though not exclusively, useful for surfacing concrete. Broadly, the present invention is concerned with an improved machine over that disclosed and claimed in my prior Patent No. 2,862,427.

A principal object of the present invention is to provide a concrete finishing machine which incorporates all of the advantages of my prior machine while having an improved range of use and flexibility.

More particularly it is an object of the invention to provide an improved concrete finishing machine which employs the combined action of wiper blades and positively driven rollers with means for adjusting the respective implements relative to each other so that the machine can be used in the finishing of concrete whose surface condition may range from relative plasticity to an extreme hardness normally incapable of being treated by surface finishing machines now available to the trade.

More specifically, it is an object of the invention to provide an improved concrete surfacing machine of the foregoing nature wherein the weight of the machine is borne by the combined support of rollers and blades and wherein means are provided for changing the proportion of the total load borne by each type of implement depending upon the hardness condition of the surface being treated.

Still another object of the invention is to provide a machine of the foregoing nature which completely finishes a concrete surface in a single operation and at a greater rate of speed with less deterioration of the surfacing implements than any machine now available to the trade.

Still another object of the invention is to provide a machine which is capable of surface treating concrete having a higher coarse-aggregate to cement ratio than can be effectively treated by machines of the prior art.

The foregoing and other objects of the invention will become apparent when the following detailed description is read in conjunction with the accompanying drawings wherein:

FIG. 1 is a perspective View of a power-driven rotary surfacing machine embodying the present invention;

FIG. 2 is a horizontal plan view showing the cooperating blades and rollers of the invention;

FIG. 3 is an enlarged vertical cross sectional view taken substantially on the line 3-3 of FIG. 2;

FIG. 4 is a vertical cross sectional view taken substantially on the line 4!- of FIG. 3; and

FIG. 5 is a diagrammatic view illustrating the combined action of a roller and a cooperating blade on the surface of concrete.

Referring now to the drawings, FIG. 1 illustrates a rotary surfacing machine constructed in accordance with the invention. Basically, the machine of FIG. 1 and several of the components thereof, including the driving means therefor, are similar to the corresponding parts disclosed in Patent No. 2,862,427, and reference is made to said patent for a detailed description of the operating mechanism of the present invention.

Briefly, the machine, so far as it is similar to the machine of the patent, consists of a non-rotatable base member mounting a driving motor 12 and carrying a handle member 14. Radiating from the base member 10 are a plurality of struts 16 which support at their outer ends a circular guard member 18. Driveably connected to the motor 12 is a rotatable hub member 2% having 3,13%,653 Patented Apr. 28, 1964 radiating therefrom a plurality of roilers 22 which are driven orbitally about a vertical axis in the direction of the arrow 24 as a result of rotary movement imparted to the hub member 20 through the operation of the motor 12. As the rollers are moved orbitally they are, at the same time, positively driven about their longitudinal or horizontal axes in the direction of the arrows 26 at a greater rate of speed than their natural rolling speed and in the same direction thereof by positive driving means confined within the rotatable base member 26. Desirably, the positive driving means can be substantially similar to that disclosed in the above-mentioned patent and may consist of a stationary ring gear within hub 2'3 and individual pinions fixed to the shafts 28 of each of the rollers. As thoroughly explained, in the aforementioned patent, the compound rotary movement of the rollers exerts on the surface of the concrete a combined vibratory and smoothing action which is unique in the art of surfacing concrete.

Because the rollers have merely line contact with the surface being treated, it will be apparent that on a surface having a fairly high degree of plasticity, the rollers would have a tendency to sink down into the surface and be wetted by the relatively soft concrete on both sides of the line of contact so that as the rollers are positively driven in their natural rolling direction but at greater than rolling speed, the increased wetted surface of the rollers tends to pick up the concrete and produce an undesirable stippled effect. In addition, where the concrete surface is soft the desired vibratory effect described in the patent is damped by the concrete so that coarse aggregate is not as effectively driven beneath the surface as occurs where the concrete has set up to a relatively high degree of hardness. These undesirable effects are entirely eliminated by the machine of the present invention.

In accordance with the invention, the present machine includes a plurality of blade assemblies 30 which radiate outwardly from the rotatable hub member 2t) substantially midway between adjacent rollers. Each of the blade assemblies consists of a blade element 32 which is arcuate in cross section and is rockingly attached by means of a pair of radially spaced bracket members 33, 34 to a shaft member 36 whose inner end 38 is pivotally connected by a stub shaft 4% between a pair of spaced cars 42. The inner vertical edges of the ears 42 are welded to the short vertical leg 44 of an L-shaped bracket member 46 whose elongated horizontal leg 43 extends over the shaft member 36 and affords an upper abutment for a pair of spaced spring elements 56, 52 interposed between the upper surface of the shaft member 36 and the leg 48 of bracket 46. The lower ends of the springs 50, 52 engage spring guides 54, 56 welded or otherwise attached to the upper side of the shaft member 36 and the upper ends of the springs 54), 52 engage spring guides 58, 66 which may be adjusted towards or away from the shaft member 36 so as to adjust the compression of springs 50, 52, for purposes to be described, by means of adjusting screws 62, 64 which extend downwardly through suitable threaded openings in the leg 48 of bracket 46 to abut the guides 58, 60.

Each blade assembly may be adjustably attached to the rotatable hub member 20 in any of a variety of ways, a preferred means including a pair of vertically spaced machine screws 66, 68 which extend through vertical slots 70, 72 in leg 44 of bracket 46 and engage threaded holes in a boss 74 welded to the outer surface of the hub member 29.

The attack angle of the blades 32 may, if desired, be adjustably fixed at a particular angle through the use of clamping screws 76 which extend through threaded holes in the bracket members 33, 34 to bear on to the shaft member 36 to retain the blades 32 at the selected angle of attack. On the other hand, where the concrete surface being worked is particularly rough it may be desirable to permit the blades to yield about their radial axes and this is accomplished in accordance with the invention by the provision of spring means 80 which are interposed between a guide 82 adjacent the upper rear edge of the blade 32 and a guide 84 fixed to the underside of a horizontal bracket member 86 welded or otherwise attached to the shaft member 36. Attached to the forward side of the shaft member 36 is a downwardly extending stop member 33 which is engageable by the upper surface of the blade member 32 to limit its movement in a clockwise direction in FIG. 4 under the influence of spring 80. With this arrangement it will be seen that when an obstruction, such as an oversize piece of aggregate, is engaged by a blade 32, it is caused to rotate about its longitudinal axis in a counterclockwise direction in FIG. 4 against spring 80 which, as soon as the blade is clear of the obstruction, causes the blade to be returned to the position in which it engages the stop member 88. In the event the obstruction is of a size which might cause the lade to be bent despite the yielding effect of the spring 86, additional yield means are afforded by the pivoted rod 36 and the springs 56, 52 between the upper side of the rod 36 and the leg 48 of the bracket 46. Where the blade is clamped at a particular attack angle by means of the clamping screws '76, the springs 56, 52 afford the only yield means for the blade 32 and it will be apparent in FIG. 3 that when the blade engages an oversize obstruction, the rod 36 will be pivoted upwardly about stub shaft 40 compressing the springs 50, 52 which immediately restore the blade to its normal working position after the blade has passed clear of the obstruction.

In operation, after the concrete has been poured and allowed to set up to a proper condition for working but where the surface of the concrete may still have a high degree of plasticity, the machine of the invention is first prepared for use by being placed on a flat surface with only the rollers initially in actual engagement with the surface. Thereafter the blade assemblies 30 are loosely connected to the rotatable hub member by the attaching screws 66, 68 being partially screwed into the bosses 74 and after all of the blade assemblies are thus positioned so that the blades are in engagement with the flat surface, the operator may then press downwardly against the upper arm 48 of the L-shape bracket 46 to cause the springs 56, 52 to be partially compressed with the entire bracket 46 being enabled by slots 70, 72 to move in the direction of the flat surface. Thereafter the operator tightens the screws 66, 68 to retain the bracket 46 in its depressed position. When the downward force exerted by the operator is released from the top of the bracket 46, the springs 50, 52 tend to expand thereby causing the blade 32 to partially share the load formerly borne entirely by the rollers. Should the expansion of the springs cause the shaft 36 to be inclined excessively it may be brought to a horizontal position by suitable adjustment of the screws 62, 64. For example, if the outer end of the shaft were above the horizontal the shaft could be rotated downwardly about stub shaft 40 merely by screwing down the outer screw 62 so as to increase the compression of spring 50. As the shaft 36 is moved downwardly, the stub shaft 46 and hence the entire hub would tend to move upwardly so that weight carried by the rollers would be decreased and shifted to the blades. If desired, the stub shaft could be engaged by a vertical slot in the end 38 of shaft 36 and the same result would be achieved as just explained, though the shaft would not normally become inclined. In practice, the arrangement shown in FIG. 3 has proved entirely satisfactory and the pivoted shaft in combination with the adjustable springs 50, 52, alfords a floating connection between the blades and the hub member 20 which accomplishes the desired result. The machine may then be placed on the surface of the concrete and the motor 12 may be started to drive the rotatable hub member 29 and hence the rollers 22 and blade assemblies 30 in the direction of the arrow 24 while, at the same time, the rollers are positively driven about their axes in the direction of the arrows 26 as previously explained.

As diagrammatically illustrated in FIG. 5, as the rollers progress over the surface of the concrete, a vibratory action in the direction of the arrow ensues so that the coarse aggregate, indicated by the numeral 92, ahead of the roller is driven beneath the surface of the concrete 94 and if the concrete surface is sufiiciently plastic, it may be stippled by the action of the roller as indicated at 96. However, with a blade 32 immediately following the roller any stippling on the surface caused by the roller is immediately smoothed by the blade to produce a perfectly flat surface as indicated at 98. To insure that the smooth surface 98 is not again stippled by the next following roller, the blades 32, as clearly indicated in FIG. 2, extend radially outwardly beyond the periphery of a circle described by the ends of the rollers. Thus, as the machine progresses over the surface of the concrete every part of the treated surface is last-engaged by that part of the blade end which extends beyond the circle described by each roller, and the surface of the concrete is therefore left with a perfectly smooth surface with any stippling effect produced by the rollers entirely removed.

In the event that the initial compression of the springs 50, 52 was initially insufficient so that the rollers tend to sink down into the surface of the concrete further than is desirable, additional load can be removed from the rollers and transferred to the blades merely by rotating the adjusting screws 62, 64 in a direction causing the spring guides 58, 66 to move toward the shaft 36 thereby compressing the springs 50, 52 so that a greater portion of the weight is carried by the blades 32, or if desired the entire assembly may be moved downwardly by readjusting the screws 66, 68. In the event that the surface of the concrete is extremely rough, the attack angle adjusting screws 76 can be loosened so that the blade can yield in both horizontal and vertical planes. On the other hand, if conditions warrant the attack angle may be set as desired by merely screwing in the clamping screws 76.

Depending upon the degree of hardness of the concrete surface, the proportion of the weight load borne by the rollers may be varied as necessary by suitable adjustment of the screws 66, 63 and/or 62, 64 with a greater proportion of the load being placed on the rollers as the hardness of the surface increases, with substantially all of the load being transferred to the rollers where the concrete surface has acquired a dry skin of some substantial thickness. Regardless of the surface condition and consequent load proportion carried respectively by the rollers and blades, where each engages the surface the beneficial effects of both are achieved. For example, in especially soft concrete, the rollers are supported against sinking into the concrete and the blades afford a reaction surface so that the desired vibratory action is achieved by the rollers sufficient to strike and drive down below the surface, coarse aggregate which is protruding thereabove, with the blades in addition to affording a reaction or supporting surface also serving to smooth the relatively soft concrete surface which the rollers might not effectively do by themselves. Obviously, where the concrete is sufficiently hard to afford a reaction surface by itself, the need for the blades to provide this function is substantially eliminated and if the concrete surface is exceptionally dense, the roller-s then perform the smoothing action themselves, as explained in my prior patent.

Where the machine is to be used on relatively soft concrete, it is desirable that the vibratory roller action be not applied in one particular location for a prolonged period lest a pulverizing action take place on the surface of the concrete. The blades provide an additional important function in preventing this in that the responsiveness of the machine to up or down maneuvering pressure on the handle increases as the proportion of the total load carried by the blades increases. Hence, under particularly soft concrete surface conditions where the blades would carry a large proportion of the load, the operator is enable to maneuver the machine quickly from place to place so that the rollers perform their important function but do not remain in one spot too long so as to possibly damage the surface. Where the surface has set-up to a higher degree of density so that greater load is borne by the rollers it is desirable that the rollers operate longer on any particular spot and the responsiveness of the machine to movement is desirably lessened by decreased load on the blades and increased load on the rollers. Proportionate maneuverability afforded by varying blade loading in accordance with surface conditions is an important feature of the invention where the machine is to be employed by inexperienced labor.

The use of rollers operating as described herein and in my prior patent have in actual use been found particularly suitable for treating concrete having a higher coarse-aggregate to cement ratio than can be treated by machines now available to the trade. The machine of the present invention is an improvement over the machine of the patent in that it enables the user to use and treat high coarse-aggregate concrete whose surface condition may range from relatively soft plasticity to almost total hardness. Consequently, by the use of the machine of the present invention, the user can select the time for working the surface which is most suitable to him, varying from a short while after pouring to several hours and even an entire day. Thus the user can schedule regular hours for accomplishing the required Work and need not fear losing a job because of unexpected rapid setting up of the concrete.

It should be noted that the described means for varying the relationship between the blades and rollers of the machine of the present invention is exemplary only and any of a wide variety of other means could be readily employed. Though the machine of the invention has been described in connection with treating concrete and it is Well suited to this use, this is by no means intended to be a limitation on the uses of the machine inasmuch as it is susceptible of treating a wide variety of surfaces by merely changing the working surfaces of the rollers and blades. For example, the rollers might be provided with a rough abrading surface and the blades provided with a finishing abrading surface with the relative radial lengths of the rollers and blades being selected which accomplishes the desired results. The machine of the invention is susceptible of the foregoing and other changes and modifications without departing from the scope and spirit of the appended claims.

What is claimed is:

1. A machine for treating surfaces comprising a rotatable hub member, a plurality of horizontally disposed rollers extending radially outwardly from said hub member and adapted to engage a surface to be treated, means for driving said rollers and said hub member about its vertical axes, means for driving said rollers about their horizontal axes at a greater rate than their natural rolling speed and in the same direction thereof, a plurality of shafts extending outwardly from said hub member between said rollers, each of said shafts being pivotally connected at its inner end with said hub member, spring means acting on said shafts to urge them towards the engaged surface, a blade member rockingly attached to each of said shafts so as to be rockable about the axis thereof, other spring means normally urging said blades in a direction causing them to produce a diverging angle of attack With respect to said surface, and stop means engageable with said blades for limiting the angle of attack thereof. 1

2. A machine for treating surfaces comprising a rotatable hub member having a vertical axis, a plurality of horizontally disposed rollers extending radially outwardly from said hub member and adapted to engage a surface to be treated, means for driving said rollers and said hub member about said vertical axis, means for simultaneously driving said rollers about their horizontal axes at a greater rate than their natural rolling speed and in the same direction thereof, a plurality of horizontally disposed wiper blades extending radially outwardly from said hub between said rollers, pivot means hingedly connecting the inner ends of said blades to said hub whereby said blades are movable in vertical radial planes with respect to said hub, and spring means acting on said blades to urge them at all times downwardly about the pivot means and in the direction of the surface to be treated.

3. The machine of claim 2 including means cooperating with said blades and said hinge means for adjusting the angle of attack of said blades.

4. The machine in accordance with claim 2 wherein said spring means are of the compression variety and including means for varying the compression of said spring means.

5. The machine in accordance with claim 2 wherein the outer ends of said blades extend radially beyond the other ends of said rollers.

6. A machine for treating surfaces comprising a rotatable hub member, a plurality of horizontally disposed rollers extending radially outwardly from said hub member and adapted to engage a surface to be treated, means for driving said rollers and said hub member about its vertical axes, means for driving said rollers about their horizontal axes at a greater rate than their natural rolling speed and in the same direction thereof, a plurality of shafts extending radially outwardly from said hub member between said rollers, each of said shafts being pivotally connected at its inner end with said hub member, spring means acting on said shafts to urge them in vertical radial planes downwardly with respect to said hub member, a blade member rockingly attached to each of said shafts so as to be rockable about the axis thereof, and means for adjustably fastening each of said blades to its shaft so as to retain the blades in a selected angular position of attack about the longitudinal axis of said shaft.

7. The machine of claim 6 wherein the pivotal connection of said shafts with said hub member include an inverted L shaped bracket having vertical and horizontal legs, each of said shafts being pivotally connected to the lower end of the vertical leg of said bracket, and means cooperating with said vertical leg and said hub member for adjusting the vertical position of said bracket with respect to said hub member, said spring means being interposed between the horizontal leg of said bracket and said shaft.

References Cited in the file of this patent UNITED STATES PATENTS 2,108,470 Boulton Feb. 15, 1938 2,342,445 Allen Feb. 22, 1944 2,434,408 Huffman Jan. 13, 1948 2,862,427 Talbott Dec. 2, 1958 

2. A MACHINE FOR TREATING SURFACES COMPRISING A ROTATABLE HUB MEMBER HAVING A VERTICAL AXIS, A PLURALITY OF HORIZONTALLY DISPOSED ROLLERS EXTENDING RADIALLY OUTWARDLY FROM SAID HUB MEMBER AND ADAPTED TO ENGAGE A SURFACE TO BE TREATED, MEANS FOR DRIVING SAID ROLLERS AND SAID HUB MEMBER ABOUT SAID VERTICAL AXIS, MEANS FOR SIMULTANEOUSLY DRIVING SAID ROLLERS ABOUT THEIR HORIZONTAL AXES AT A GREATER RATE THAN THEIR NATURAL ROLLING SPEED AND IN THE SAME DIRECTION THEREOF, A PLURALITY OF HORIZONTALLY DISPOSED WIPER BLADES EXTENDING RADIALLY OUTWARDLY FROM SAID HUB BETWEEN SAID ROLLERS, PIVOT MEANS HINGEDLY CONNECTING THE INNER ENDS OF SAID BLADES TO SAID HUB WHEREBY SAID BLADES ARE MOVABLE IN VERTICAL RADIAL PLANES WITH RESPECT TO SAID HUB, AND SPRING MEANS ACTING ON SAID BLADES TO URGE THEM AT ALL TIMES DOWNWARDLY ABOUT THE PIVOT MEANS AND IN THE DIRECTION OF THE SURFACE TO BE TREATED. 